Regulatory policies affecting global agrochemical formulations & adjuvants and their impact on formulation development

José Luis Garido – Scientific Expert - Physical Chemistry and Analytical Methods at SynTech Research Group 

The regulation of agrochemical formulations and adjuvants is a critical topic in the global agricultural industry. These regulations influence product development, market access, and compliance requirements, impacting stakeholders from manufacturers to farmers. With increasing concerns about environmental sustainability, human health, and product efficacy, authorities worldwide continue to refine policies governing agrochemicals.

Regulatory Updates on Agrochemical Formulations & Adjuvants – Europe

Regulatory policies in Europe continue to evolve, particularly regarding co-formulants and adjuvants in plant protection products (PPPs). Under Article 2(3)(c) of Regulation 1107/2009 (PPPR), co-formulants are defined as substances used in PPPs that are neither active substances, safeners, nor synergists.

A key development is Commission Implementing Regulation (EU) 2023/574, which outlines strict criteria for identifying unacceptable co-formulants. From April 3, 2023, all applications for PPP authorization, modification, or renewal must undergo checks for these potentially harmful co-formulants. If a co-formulant meets any of the ten criteria specified in the Annex of (EU) 2023/574, it may be classified as unacceptable due to its (eco)toxicological properties, leading to its inclusion in Annex III and eventual restriction or phase-out in the EU.

Adjuvants, which fall under Regulation (EC) No 1107/2009, must also be authorized before market placement, as stipulated in Article 58 of the PPPR. However, because no harmonized EU-level requirements exist, individual Member States regulate them under national legislation until a standardized process is established.

Additionally, the European Union has been progressively strengthening its regulatory framework to limit hazardous substances in agrochemical formulations. Regulation (EU) 2021/383, effective since March 24, 2021, established restrictions on the presence of hazardous substances in adjuvants, ensuring safer formulations. Building upon this, the Commission adopted Regulation (EU) 2024/1487 on May 29, 2024, introducing new data requirements for safeners and synergists. As part of the implementation, companies must notify the Commission by December 19, 2024, regarding safeners and synergists present in PPPs that were authorized in at least one Member State by June 19, 2024. This notification process aims to create an initial inventory of these substances on the market. Looking ahead, by June 19, 2028, companies will be required to submit formal approval applications for these substances to the designated rapporteur Member State (RMS). 

Challenges in Registration of Plant Protection Products in Europe

Physicochemical Properties

The physicochemical properties of plant protection products are essential for ensuring their efficacy, stability, and compliance with regulatory standards. The guidance document SANCO/10473/2003 – rev.5 provides the framework for generating and evaluating data on the physical, chemical, and technical properties of these products under the PPPR.

Different formulation types require distinct data sets, which, while similar, are not identical to those outlined in the FAO manual for other regions. The selection of co-formulants significantly influences formulation parameters, affecting stability during various storage tests, including accelerated storage, shelf life, and low-temperature stability assessments.

During storage stability studies, if an active substance experiences a loss of more than 5%, the degradation pathway must be identified, and breakdown products must be assessed. If the loss exceeds 10% during accelerated studies, interim ambient storage data must be submitted to determine degradation kinetics and establish an appropriate shelf life. Additionally, the potential impact of packaging materials on formulation stability is outlined in CropLife International Monograph 17, emphasizing the need for detailed reporting on any observed changes following storage.

Analytical Challenges

The complexity of agrochemical formulations presents significant analytical challenges during the registration process. Regulatory authorities require precise and reliable methods to identify and quantify active substances, impurities, and co-formulants within plant protection products. SANCO/3030/99 rev.5 serves as the primary guidance document for generating and reporting analytical methods, ensuring consistency and reliability in pre- and post-registration data submissions.

Classification and Labelling

Effective chemical management relies on clear classification and labelling, ensuring both safety and regulatory compliance. The EU’s Classification, Labelling, and Packaging (CLP) Regulation, built on the United Nations' Globally Harmonized System (GHS), plays a crucial role in protecting health and the environment while supporting the smooth trade of chemicals across borders. By requiring manufacturers, importers, and users to properly classify, label, and package hazardous chemicals before they reach the market, the regulation helps maintain consistency and transparency in the industry.

With evolving scientific understanding and regulatory priorities, updates to the CLP framework continue to shape how chemicals are assessed. Regulation (EU) 2023/707, an amendment to CLP Regulation (EC) No 1272/2008, introduces new classification criteria set to take effect in May 2025 for substances and May 2026 for mixtures. As companies navigate these changes, it is essential to proactively evaluate how classification updates might impact their formulations. 

Environmental Fate and Ecotoxicology

Understanding how chemical substances behave in the environment is essential for both regulatory compliance and sustainable product development. As of July 14, 2023, new EU guidance requires manufacturers to assess how water treatment processes affect active substance residues in drinking water sources. This added layer of scrutiny means additional testing, higher regulatory costs, and the need for more strategic planning. Companies must refine their testing approaches to balance compliance with efficiency, as substances that generate harmful transformation products could face severe restrictions or even bans.

Beyond water treatment considerations, the regulatory framework also evaluates how substances interact with different environmental compartments—soil, groundwater, surface water, and air. Predicted Environmental Concentrations (PEC) must be assessed to determine potential risks, while risk evaluations for formulated products take into account application rates, plant growth stages, and environmental conditions. If non-target organisms are at risk, mitigation strategies such as application restrictions or additional protective measures must be put in place to guarantee a safe use.

Toxicological Considerations

Ensuring the safety of co-formulants is a critical aspect of regulatory compliance and product development. Under Regulation (EU) 284/2013, all co-formulants must undergo rigorous evaluation to assess their potential health risks. In 2021, the adoption of Regulation (EU) No 383/2021 led to the prohibition of 144 substances in plant protection products (PPPs), reflecting growing concerns over toxicity and environmental impact.

For substances not included on the exclusion list, further scrutiny is required under Regulation (EU) No 574/2023. This assessment examines key toxicological properties, including mutagenicity, carcinogenicity, reproductive toxicity, endocrine disruption, and PBT (persistent, bioaccumulative, and toxic) characteristics.

Residues and Efficacy

In the EU, residue data requirements generally remain unaffected by the specific formulation of a product. However, when substituting formulations in residue trials, bridging studies must demonstrate comparability to ensure the safety and effectiveness of the new formulation. Whether or not further data is required for extrapolations depends on factors such as the formulation type and the conditions under which it is applied.

For efficacy trials, it is essential that they are conducted using the final formulation, with only minor adjustments permitted without necessitating additional testing. Moreover, the requirements for bridging trials can vary across EU Member States, as they are subject to expert assessments. 

Regulatory Updates outside of Europe – USA and Latin America

Regulatory developments outside Europe are shaping the landscape for agrochemicals and their formulations. For instance, in the United States, the Environmental Protection Agency (EPA) classifies adjuvants as "other ingredients" within pesticide formulations. While the EPA reviews these ingredients during registration, it does not impose specific registration requirements for them. To help navigate this process, the EPA offers tools like InertFinder, which assists in identifying permissible inert ingredients based on their intended use.

Recent EPA regulatory actions include:

• A proposed ban on N-Methylpyrrolidone (NMP) in agrochemical formulations.

  
  

• Ongoing investigations into PFAS contaminants in agrochemicals following third-party testing claims.

  
  

• A prohibition on fluorinated packaging for agrochemicals.

  
  

• The implementation of biostimulant regulations in California, with expectations for similar measures in other states.

  
  

• A push to reduce off-site agrochemical movement due to EPA's Endangered Species review, prompting industry efforts to reformulate products and improve application technology.

In addition to the regulatory shifts in the United States, Latin America presents a unique landscape for agrochemical formulations. While countries in the region may not have specific regulations for adjuvants, the regulatory environment still reflects a global push toward safety and compliance. For example, Brazil removed adjuvants from its agrochemical regulations in 2017, effectively leaving them unregulated. Similarly, many other Latin American countries lack specific adjuvant regulations, which creates a regulatory gap that manufacturers need to navigate.

However, it is important to note that substances restricted or banned in major markets like the EU and the USA cannot be used in Latin American countries either, reinforcing the importance of aligning with international standards to ensure compliance across borders, especially as global trade and regulatory scrutiny continue to evolve.

The regulatory landscape for agrochemical formulations and adjuvants continues to evolve across regions. While the EU tightens restrictions on co-formulants and adjuvants, the USA focuses on environmental and safety concerns, and LAM countries follow global regulatory trends. Industry stakeholders must navigate these complex requirements, optimize formulation strategies, and ensure compliance with evolving regulations to maintain market access and product efficacy.

Contact SynTech Research Group:

info@syntechresearch.com

Dr. José Luis Garido has delivered a speech with this topic at AgroPages' event - 5th Ag Formulation & Application Technology Congress (FAT 2024), during Nov. 26-27, 2024 in Hangzhou, China.

Click here to view the report for FAT 2024.

Know more about 6th Ag Formulation & Application Technology Congress (FAT 2025), or you'd like to share your valuable perspectives with us, please contact:

Grace Yuan

Tel: +86 15505713266（WeChat）

Email: grace@agropages.com